Extent of compression is defined by the relation of full volume of a cylinder to fuel combustion chamber volume. In other words, it shows how much density of fuel-air mix when moving the piston from the lower dead (extreme) point in the top dead point will be increased. Extent of compression of the engine of the car pays off and defined at its design.
Instruction
1. The extent of compression in the engine is higher, the car has to use higher than an octane number of fuel. For example, racing race cars use methanol and have extent of compression 15 and above. Decrease in degree is used in cars for increase in their power. Especially it concerns turbo engines with boost. The boost pressure is higher, the below there has to be extent of compression since the volume of injectable fuel and the arriving air increases.
2. Extent of compression is lowered and to raise a threshold of detonation of the engine and to receive optimum angles of advancing of ignition. For example, it is possible to increase combustion chamber volume, however it is impossible to achieve a significant change in size. Is possible only to clean keen edges, to smooth wells valves, to commit other operations, that will give gain only in several cm3 and respectively decrease degree compression only on slightly tenth.
3. Pierce a piston bottom. However factory have a thin bottom and it is essential to change them it is impossible. Therefore this method is applicable only when units in the engine are manufactured to order.
4. Establish laying (pro-rate) under a head of the block of cylinders. She represents a thick metal plate and repeats a head surface configuration. Laying can be bought ready prepared, it is possible to turn independently. Having established it, you raise a block head above the top dead point, increasing, thus, the volume of cylinders. It, in turn, increases amount of the fuel mix getting there, gives larger explosion in the camera that leads to increase in torque.